UWB technology is a new exploration of the use of radio spectrum resource and it inaugurate a new field of time domain application of electromagnetic wave.

利用UWB技术是对无线频谱资源的利用进行的新的探索，开辟时域电磁波应用的新领域。

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Spectrum of the amplitude-modulated wave is observed by a radio frequency spectrum analyzer and amplitude values of every spectrum are recorded at the upper sideband or lower sideband.

用射频频谱分析仪观测一个已调波的频谱成分，记录上边带或下边带中各条谱线的幅度值，从而可以根据有关算式计算出调制信号（音频信号）的失真度。

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His father demanded a lower-quality vocoder that would spare precious radio-wave spectrum.

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